Battery Switch Operation

[petern]

I'm in the habit of leaving the battery switch in the "both" position on, 24/7, including at the dock with shore power.

Is this OK, or should I be handling this differently?

Thanks for the help!

 

[MLauman]

I only put mine on BOTH when I need the extra power to start the engine or I wish to charge both batteries from the alternator. It's been years since I've needed either scenario (but I have a genset).

IMO, you should always keep the switch on 1 or 2 while on the boat with the motor off. That way you are assured that the other battery is sufficient to start the engine should you run one down.

If your batteries are identical types then you should rotate them each time you go out. However, you might have designated 'starting' and 'deep cycle' batteries and should then use them as indicated.

A properly wired shorepower battery charger will charge both batteries regardless of switch setting - even OFF.

 

[Henry Boyd]

The switch can in any position (1,2,both, off) and the charger will still charge both batteries. On single engine boats, both batteries should be the same type of battery. There is no separate house and engine circuit. The batteries are either isolated (1 or 2, or Off) or connected in parallel (both). If you had a cranking battery and deep cycle for example, they would never charge properly when used in the both position (or when on the shore power charger) because the charging profiles are different.

Henry

 

[boatmailster]

I'm in the habit of leaving the battery switch in the "both" position on, 24/7, including at the dock with shore power.

Is this OK, or should I be handling this differently?

Thanks for the help!

Bad idea. When you "kill" all batteries how are you going to start engine?

 

[petern]

thanks guys....it only makes sense once thought through......battery 1 or 2 when anchored. matters not when on shore power.

 

[Dave S]

On mine, once I am hooked to shore power I turn my switch OFF. There is no reason to leave it on since all the critical things like the Bilge pumps are wired directly to the battery and will have power regardless.

Dave

 

[rcmafgny]

i do the same as dave